Bounced e-mails: why?

I recently joined a local branch of a National educational organisation with a very fast growing membership (The University of the Third age (U3A)). Within the local branch there are many educational subgroups meeting weekly, bi-weekly or monthly. The national website allows the webmaster of each branch to place group and event information onto the local website.

By accident I became newsletter editor. Up to that point the then chair was editing the newsletter and printing it at home, an A5 booklet with about 3 sheets of A4 for 65 members. Membership is now over 150 and I do not have the time nor the print facilities to do this type of production and since about 65% of the membership had supplied an email address I suggested we consider emailing the newsletter - which is where the problem stated.

I was advised to use a piece of software called MailChimp. It was easy to cut and paste the email address and names into MailChimp and I then set up a basic 'hello is the email address right and do you want your Newsletter this way' email.

MailChimp removed duplicate emails addresses - husband and wife couples who shared the address - no problem. Then I received bounce-backs. MailChimp deletes these entries so no problem with the membership database but I do now have a problems with the bounce backs.

Most of the bounces were simple typos from reading the original handwritten address but I now have 10 emails where I have the correct address and it still bounces.

I know the 10 are correct. I got the owner to email me and I then replied. The owner confirmed that they had received my reply. So I cut and pasted the address from their email into MailChimp, sent the first Newsletter and these 10 bounced back again. Why?

I cannot see any pattern, there are 8 different ISP's with only hotmail appearing 3 times. One person in particular has said that I am not the only one who has this problem although most other people seem to be able to send to her. I have wondered if the emails which get through are replies but I did not think to ask that question, perhaps I should! Even so that does not define the basic problem with the email delivery!

Finding the bounce reason and deciphering the numeric code

If you're wondering where to find the bounce reason when one doesn't appear in the bounce e-mail text, it's probably in the .dat attachment of the bounced e-mail. To read it, save the .dat attachment to your desktop, then open as a textfile (with Notepad, Wordpad, Microsoft Word or whatever). Or you could associate .dat files with one of these programs (I do).

The list of mystic numeric bounce codes on p2 of this article is sometimes needed.

The circumstances would seem to point to the possibility that some of the receipients have MailChimp emails block either a blacklist or spam filter. Since emails done manually with your account work, there's something about the way mailchimp is doing it.

I tend to agree with pcmechanic: MailChimp has something in it that make other clients consider it as a sender of spam. A common response by some clients to this consideration is to automatically bounce and delete it from the PC.
As Roderunner suggest: Try another client. In fact: Try several. When You find one You like, adapt it as standard.
I've used Incredimail for twelve years and have become very comfortable with it. One should have a client that gives no problems, manned with good support behind - just in case.